1. Field of the Invention
The present invention relates to a photoreceptor unit and an image forming apparatus, and particularly to a photoreceptor unit inserted into an image forming apparatus in a predetermined insertion direction and the image forming apparatus.
2. Description of the Related Art
Japanese Laid-Open Patent Publication No. 2006-267808 (Document 1) discloses a process cartridge for a printer and the like provided with a cover member having a two-layered structure which includes a cushioning sheet protecting a photoreceptor drum and shielding the photoreceptor drum from light, and a cover sheet removed from a cartridge body together with the cushioning sheet at the time when the cartridge body strikes against the external wall of the body of an image forming apparatus.
Furthermore, Japanese Laid-Open Patent Publication No. 2007-271759 (Document 2) discloses that the sheet-shaped packaging material enclosing a process cartridge is connected to a separation cover that is detachably attached to the body frame of the process cartridge.
When a photoreceptor unit including a photoreceptor drum is inserted into an image forming apparatus, it is desirable to provide a rigid cover that is resistant to the pressure applied by the user's operation in order to protect the photoreceptor drum from the applied pressure. However, it is not preferable in terms of resource saving to provide a rigid cover on the entire photoreceptor drum.
The process cartridge disclosed in Document 1 includes a cover member formed only of a sheet-shaped member, which is completely different in precondition and configuration from the present invention provided with a rigid cover member.
Furthermore, the process cartridge disclosed in Document 2 aims at reducing distortion and sliding friction of a charging roll, and does not necessarily serve to fully solve the above-described problems.